In recent years there has been a change in attitude particularly with PC runs. There are still happenings like Cuphead where the devs patch everything useful and split the leaderboards into current patch and legacy versions of the game, but it seems they're starting to realise that having a bunch of autists give exposure to your game years after release is kind of valuable.
Celeste is maybe the best example. The game is basically designed for speedrunning, and after people started finding stuff in the game to skip various things, the devs encouraged it and even attended GDQ to commentate on one of the races there. They also put a couple of things in the game after release to make a couple of slow parts of the game faster. One of the largest skips in the game was found by the devs before release and they just kept it in.
I love how they're constructive right away. Having toggleable exploits to doing an in depth look at working these out, they keep being positive about it. Sounds like a fun crew of guys to work with.